QuakeIndex

Earthquake · reviewed by a seismologist

M 1.8ml

3 km S of Southworth, Washington

· 25 km deep · released about 14 lb of TNT

10 km30 km60 km120 km N Kitsap County 21 kmKing County 50 kmMason County 53 kmPierce County 54 kmThurston County 66 kmIsland County 76 kmSnohomish County 84 kmJefferson County 85 kmLewis County 101 km
Distance rings around the epicentre, with the nearest towns at their true direction and later quakes as coloured dots. Not a shaking map — see the USGS ShakeMap for that.
When
Magnitude
M 1.8 (ml)
Depth
25 km below the surface
Felt
no reports yet
Nearest
Kitsap County, 21 km NNW
Status
Reviewed by a seismologist

USGS · last changed by USGS · we first saw it 776 days ago

This was a minor earthquake. Quakes this small are rarely felt and do not cause damage.

How big was it?

This earthquake released about 14 lb of TNT. Magnitude is logarithmic: each whole step up releases about 32 times more energy, so a magnitude 2.8 would have released about 32 times as much.

  1. Mineral, Virginia 2011 M 5.8 1,100,000× the energy of this one
  2. Magna, Utah 2020 M 5.7 760,000× the energy of this one
  3. Around the size people start to feel M 3.0 68× the energy of this one
  4. This earthquake M 1.8 about 14 lb of TNT

Energy from the Gutenberg–Richter relation (log10E = 1.5M + 4.8), rounded to two figures; bar length is magnitude, which is already a logarithm of energy. Magnitudes of past earthquakes from the USGS catalogue.

Where

Epicentre 47.4815, -122.4933. Map © OpenStreetMap contributors.

Nearby places

PlaceDistanceDirection
Kitsap County, WA 21 km (13 mi) SE of here earthquakes near Kitsap County
King County, WA 50 km (31 mi) W of here earthquakes near King County
Mason County, WA 53 km (33 mi) ENE of here earthquakes near Mason County
Pierce County, WA 54 km (34 mi) NNW of here earthquakes near Pierce County
Thurston County, WA 66 km (41 mi) NNE of here earthquakes near Thurston County
Island County, WA 76 km (47 mi) S of here earthquakes near Island County

Places and coordinates from the US Census Bureau Gazetteer (2024). Distances are from the epicentre.

Aftershocks so far

56 earthquakes have been recorded within 50 km since this one.

  1. 1.6 6 km S of Gorst, Washington
  2. 1.9 4 km WSW of Erlands Point-Kitsap Lake, Washington
  3. 2.0 2 km NNE of Boulevard Park, Washington
  4. 1.8 2 km SSE of Woodinville, Washington
  5. 3.2 7 km ESE of Maplewood, Washington
  6. 1.6 1 km ESE of Inglewood-Finn Hill, Washington
  7. 1.9 2 km E of Tracyton, Washington
  8. 1.8 2 km ENE of Tracyton, Washington
  9. 1.8 3 km E of Tracyton, Washington
  10. 1.8 3 km NNW of Enetai, Washington
  11. 1.5 2 km NNW of Enetai, Washington
  12. 2.8 0 km ENE of Tracyton, Washington
  13. 1.6 2 km NNW of Enetai, Washington
  14. 2.3 1 km NE of Lakeland North, Washington
  15. 3.4 6 km SSE of Lea Hill, Washington

Counted from the QuakeIndex database, which ingests the USGS feed every 30 seconds · as of . QuakeIndex does not forecast aftershocks. When USGS issues an operational aftershock forecast it appears on the USGS event page.

For this area

The largest earthquake within 50 km in our catalogue was M 4.1 on 2017-02-23 — it released about 2,900 times the energy of this one.

From the QuakeIndex catalogue, built from the USGS FDSN event service.

On USGS

QuakeIndex does not issue warnings. For earthquake early warning see ShakeAlert.